ML20198G632
| ML20198G632 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 12/23/1998 |
| From: | Cruse C BALTIMORE GAS & ELECTRIC CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9812290122 | |
| Download: ML20198G632 (7) | |
Text
_
CHARIES II. CRUSE Ilattimore Gas and Electric Company Vice President Ct.lvert Cliffs Nuclean Power Plant a
Nuclear Energy 1650 Calvert Cliffs Parkway Lusby, Maryland 20657 410 495-4455 December 23,1998 U. S. Nuclear Regulatory Commission Washington, DC 2055$
ATTENTION:
Document Control Desk
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit Nos.1 & 2; Docket Nos. 50-317 & 50-318 Correction to the Response for Additional Information; License Amendment Request:
One-Time Technical Specification Change to Support the 1999 Refueling Outage
REFERENCES:
(a)
Letter from Mr. C. H. Cruse (BGE) to NRC Document Control Desk, dated December 4,1998, " Response for Additional Information; License Amendment Request: One-time Technical Specification Change to Support the 1999 Refueling Outage (b)
Teleconference between Mr. J. K. Kirkwood and Mr. J. L. Stone (BGE) and Mr. D. O'Neill (NRC) on December 17, 1998, Concerning
(
Emergency Diesel Generator Reliability Parameters
/
On December 15,1998, our Plant Engineering ttaff discovered the need for us to clarify a statement in Reference (a). On page 3 of Attachment I to Reference (a), we stated, "To ensure compressed air is available, temporary (three) diesel air comp:essors are to be installed on Unit 2 compressed air and have the capability of being cross-connected automatically to Unit 1 on loss of air pressure."
Please change this statement to read, "To ensure compressed air is available, an operating temporary diesel air compressor will be connected to the Unit 2 non-safety-related compressed air system and ncrmally cross-connected to Unit 1. A second, temporary diesel air compressor in manual start will be installed as a back-up."
The third diesel air compressor was not credited in the risk analysis. Therefore, this change does not affect the core damage frequency numbers we supplied in Reference (a).
9812290122 981223 j
PDR ADOCK 05000317r P
PDR ;
_ _.. _ _.. ~, _. _. _. -... _ _ _
Document Control Desk Dec:mber 23,1998 Page 2 Also, Attachment (1) provides more current emergency diesel generator failure rate and unavailability data than was supplied in Reference (a).
Should you have questions regarding this matter, we will be pleased to discuss them with you.
Very truly yours,
/ptr /
th &
CHC/JKK/bjd 1
Attachment:
(1) Revised Emergency Diesel Generator Failure Data cc:
R. S. Fleishman, Esquire II. J. Miller, NRC J. E. Silberg, Esquire Resident Inspector, NRC S. S. Bajwa, NRC R. I. McLean, DNR A. W. Dromerick, NRC J. H. Walter, PSC Y
~..,.
t l
l i
ATTACHMENT (1)
L I
I REVISED EMERGENCY DIESEL GENERATOR l
FAILURE DATA i
l l
l Baltimore Gas & Electric Company Calvert Cliffs Nuclear Power Plant December 23,1998
ATTACHMENT (1)
REVISED EMERGENCY DIESEL GENERATOR FAILURE DATA t
NRC Ouestion 14: (originated in Reference B)
Note: The response to question #7 of Reference (1) used data for the period 1985-1991.
In the response to question #7 of Reference (1), the failure rates and unavailabilities for the Emergency Diesel Generators (EDGs) are based on data up through 1991. What would the failure rates and i
unavailabilities be if more recent data was incorporated into the failure rates? Further, what would the impact be to the overall response if the new failure rates, and unavailabilities, for the EDGs were incorporated into Calvert Cliffs Probabilistic Risk Assessment (CCPRA)?
1 BGE Response:
The EDG failure rates and unavailabilities were updated with more recent data. Generally, the data l
i used was through June of 1998. However, the data used for the Societe Alsacienne De Constructions Mecaniques De Mulhouse (SACM) EDG failure and success data is through November 1998 for the
" Fail to Start" and " Fail to Run" failure modes. The failure rates for all EDGs were Bayesian Updated with the new failure data.
)
i i
Failure Rates i
I Original Failure Description -
Failure ~
Updated ereentage Failure Rate -
ange
-- Rate.
)
Fairbanks Morse EDG Fails to Start 2.47E-03 1.44E-03
-42%
Fairbanks Morse EDG Fall to Run 3.08E-03 2.37E-03
-23%
1st Hour SACM EDG Falls to Start 4.85E-03 2.17E-03
-55%
SACM EDG Fails to Run 1st Hour 3.90E-03 4.07E-03
+4%
Fairbanks Morse Fall to Start - Beta 2.17E-02 1.87E-02
-13.8%
Common Cause Factor Fairbanks Morse Fail to Run 1st 2.79E-02 2.09E-02
-25.1 %
Hour - Beta Common Cause Factor Note: Remaining Common Cause factors were not impacted by the new data.
Unavailabilities Original Updated Percentage Description Unavailability Unavailability Change Fairbanks Morse EDGs 1.07E-02 8.31E-03
-23%
FDG 1 A (SACM) 1.34E-02 1.58E-02
+18%
EDG OC (SACM) 1.34E-02 3.81 E-02
+185%
1 j
ATTACIIMENT (1)
' REVISED EMERGENCY DIESEL GENERATOR FAILURE DATA The updated failure rates, common cause factors, and unavailabilities were incorporated into the EDG System Analysis to determine the updated Split Fraction failure rates. These updated values were incorporated into the CCPRA to determine the impact on the analysis of the proposed Temporary EDG Cooling lineups.
The benefit noted in response #1 of Reference (1) remains 1.42E-05 per year. There were no significant changes to any other response in Referene: (1). A revised Table 8A is attached. The order of the top non-screened initiating events did not change. A new column has been added to this table to show the changes between the new values and the original response. The changes are relatively small, the largest being TBMFW1 which decreased by 5.9%. Since the order of the Initiating Events did not change, the top sequences discussed in 8B were not re-evaluated.
Reference:
1.
Letter from Mr. C. II. Cruse (BGE) to NRC Document Control Desk, dated December 4,1998,
" Response for Additional Information; License Amendment Request: One-time Tech'iical Specification Change to Support the 1999 Refueling Outage l
)
i 2
ATTACHMENT (1)
REVISED EMERGENCY DIESEL GENERATOR FAILURE DATA TABLE 8A Increase Increase Delta From Initiating Initiating Event Description Over One Over 41 Screened Invalid IE Valid IE Original Event Year Days Contributions Contributions RAI
Response
1 TBMFW2 Unit 2 Steam Generator Feedwater 4.43E-06 4.98E-07 No 4.98E-07 0.2%
Turbine and Pump Fire 2
LHURI Hurricane 2.74E-06 3.07E-07 No 3.07E-07
-2.0%
3 IESF Inadvertent ESFAS actuation 2.16E-06 2.43 E-07 Yes i 2.43 E-07 0.0%
4 LOSWl1 Loss of Saltwater lleader 11 138E-06 1.54 E-07 Yes i 1.54E-07 0.0 %
5 TBALLB Main Turbine and Generator Turbine 1.23E-06 138E-07 No 138E-07
-5.4%
Building Fire 6
LOSW Loss of All Unit 1 Saltwater 1.20E-06 135E-07 Yes i 135E-07 0.0%
7 L120V1 Failure of 120 VAC Panel 11 1.10E-06 1.23 E-07 Yesi 1.23 E-07
-0.1 %
8 TBMFW1 Unit 1 Steam Generator Feedwater 7.92E-07 8.90 E-08 No 8.90E-08
-5.9%
Turbine and Pump Fire 9
LOOP 11 Loss of Offsite Power for 4 to 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> 6.09E-07 6.84 E-08 No 6.84E-08
-3.6%
10 LOISRW Loss of Service Water Header 1 ) or 12 6.01 E-07 6.75E-08 Yes i 6.75E-08 0.0 %
11 LBl1B Failure of 480 VAC Bus 1IB 4.49E-07 5.04E-08 Yes i 5.04E-08 0.0 %
13 A306FD 120VAC Inverter 12, and Transient induced 4.40E-07 4.95E-08 Yes i 4.95E-08 0.0%
inverter and vital AC panel fires 12 FCYRDB Yard Fire - 13KV Bus 21/22, P-13000-2 433E-07 4.86E-08 No 4.86E-08
-3.6%
transformer, U-4000 21 & 22 transformers 15 LTBSRW Loss of Service Water to both Turbine 4.27E-07 4.80E-08 Yes i 4.80E-08
-0.9%
Building Headers 14 LOOP 24 Loss of Offsite Power for 11 to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 4.26E-07 4.79E-08 No 4.79E-03
-0.9%
16 LB114R Failure of 480 VAC MCC 114 R 3.81 E-07 4.28E-08 Yes i 4.28E-08
-0.2%
17 LTBSRA Loss of Service Water Turbine Building 3.60E-07 4.04E-08 Yes i 4.04E-08 0.0 %
Header 11 18 LOAC4 Loss of 4 KV Bus 14 (not recoverable by the 3.58E-07 4.02E-08 Yes i 4.02E-08 0.0%
EDGs) l 19 FCYRDA Yard Fire - 13KV Service Bus and 3.52E-07 3.95E-08 No 3.95E-08 0.0%
l t
3
ATTACHMENT (1) e REVISED EMERGENCY ' DIESEL GENERATOR FAILURE DATA TABLE 8A Increase Increase De,lta From Initiating Initiating Event Description Over One Over 41 Screened Invalid IE Valid IE Original Event Year Days Contributions Contributions 1.AI l Response Transformers Area 20 LOSW12 Loss of Salt Water ficader 12 3.24E-07 3.64E-08 Yes i 3.64E-08 0.0%
21 FlAEDG Yard Fire - EDG 1 A 3.16E-07 3.55E-08 Yes 3.55E-08 0.0%
22 A306FF Cable Spreading Room Fire - 120VAC 3.07E-07 3.44E-08 Yes i 3.44E-08
-0.2%
Inverter 13, and Transient induced inverter and vital AC panel fires 23 LOCV Loss of Condenser Vacuum 2.51 E-07 2.82E-08 Yes i 2.82E-08 0.0 %
24 AUX 20A Aux Bldg Fire - 5' Multi-compartment 2.41E-07 2.71E-08 No 2.71E-08 4.1%
Area (Fire Area 1I) 25 L500B Failure of the 500 KV Black Bus 1.86E-07 2.09E-08 No 2.09E-08 2.1%
Totals 2.41E-06 l
-0.9%l 1.13E-06 l 1.29E-06
-1.8 %
Note 1).
Tnese initiating events caused increases due to the modeled unavailability of Unit 2 Service Water which fails the Unit 2 Non-Safety-Related Air Compressors. However, temporary diesel air compressors (3) are to be installed on Unit 2 non-safety-related compressed air and have the capability of being cross connected automatically to Unit 1 on loss of air pressure. Further, there will be fire hoses connected to a permanent non-safety-related air compressor to allow once through cooling of this compressor. This lineup should mitigate most of the risk increases noted for these initiating events.
4 i